The notion of stability is central to the definition of personality traits, which are generally thought of as enduring tendencies or habitual patterns of behavior, thoughts, and emotions (McCrae & Costa, 2003), but stability does not imply immutability. Under normal circumstances, adult traits are largely stable, as indicated by high correlation coefficients computed for a group assessed twice on the same trait. These coefficients represent the average stability for a sample, but individuals vary in terms of their intra-individual stability. Despite the relative stability of individual differences, we have extended the studies of mean-level change in personality by examining longitudinal trajectories in more diverse samples and cross-sectional trends across cultures. Furthermore, we aim to delineate the neural and cognitive correlates of personality dimensions across longitudinal assessments. Most recently, we have begun investigating the association between personality traits and decision making. We investigated the personality correlates of risky decision making in healthy older adults. We also continue to collect fMRI studies of brain activation during decision making and will relate personality variables to patterns of brain activation during gains and losses, as well as in relation to individual differences in risk preference. We continue to collaborate with Dr. Antonio Terracciano on studies of personality characteristics that may predict subsequent cognitive impairment and personality change during the preclinical and prodromal phases of Alzheimer's Disease (AD). In previous work, we showed that traits of high Neuroticism and low Conscientiousness were associated with increased risk for Alzheimer's disease later in life. Additionally, we examined whether personality is stable or changes during preclinical and prodromal AD. We examined 2046 participants in the Baltimore Longitudinal Study of Aging. Individuals who developed dementia scored higher on Neuroticism (=2.83; 95% CI, 1.44 to 4.22; P<.001) and lower on Conscientiousness (=-3.34; 95% CI, -4.93 to -1.75; P<.001) and Extraversion (=-1.74; 95% CI, -3.23 to -0.25; P=.02). However, the unimpaired group did not differ significantly in personality change over time from the Alzheimer disease and mild cognitive impairment groups. Thus, we found no evidence for preclinical change in personality before the onset of mild cognitive impairment or dementia. These findings provide evidence against the reverse causality hypothesis and strengthen evidence for personality traits as a risk factor for dementia.